Maybe as you do the build it is possible to fab a pvc support for the inside. It's paper so I don't see an issue cutting hols to slide pieces through. Plus adding a sealant to it will make it stiffer and like most of my props they see very little sunlight.
I was going to print this on my home printer but my buddy owns a printing business and can produce better quality so I will have home print me up about 3 of these. One to build then the 2nd to cut out detail pieces and a 3rd..no telling. I was thinking of cutting sintra and adding the detail pieces to that then attaching it to the main model